Microcrystalline silicon devices for radiation sensing applications

Abstract

Crystalline silicon (Si) of different concentration types was implanted with Aluminium (Al) and Zinc (Zn) at the energy of 160 keV to the fluence of 1.0 1017 ions cm-2. Different material characterization techniques were used to confirm the presence of Al and Zn in Si prior to device fabrication. Schottky diodes fabricated on undoped and metal-doped Si were characterized at room temperature using current-voltage and capacitance-voltage techniques to investigate a change in electrical properties of the diodes due to metal doping. The diodes were then irradiated by 3 MeV protons and recharacterized to establish a change in diode properties due to irradiation. A change in different diode parameters due to metal doping and irradiation was also investigated. The results are explained in terms of the defects that are induced by metals in Si and are important for an ongoing quest to improve the efficiency of Si radiation detectors for current and future high-energy physics experiments and other applications. For the first time, it is shown in this work that Al and Zn are suitable dopants to improve the stability and sensitivity of the devices to incident particles.